DV decoder differences

[FredThompson]

NTSC DV? Use trbarry's AviSynth filter to make a better MPEG2.

noise with DV is usually from cheap CCDs or artifacts due to 4:1:1 color of NTSC DV. Deinterlacing will always throw away half the temporal information There's no good reason to deinterlace unless you want to go back to a film source.

[bb]

Originally posted by FredThompson
[...]noise with DV is usually from cheap CCDs or artifacts due to 4:1:1 color of NTSC DV.[...]

That's true, but noise typically occurs in low-light conditions, no matter how good your CCD is. Low-light in this case refers to the amount of light the CCDs can capture, so to say "how much light gets inside the camcorder". Thus good and big object lenses can make lower-noise DV video than small ones with the same (low) light outside.

bb

[gavo]

You say that the maincopect is the worse because of the sharpen although I find it safer because of less bugs, What if you use smoothing filters in avistyn would that average it out to about the same?

[moon1234]

Originally posted by FredThompson
NTSC DV? Use trbarry's AviSynth filter to make a better MPEG2.

noise with DV is usually from cheap CCDs or artifacts due to 4:1:1 color of NTSC DV. Deinterlacing will always throw away half the temporal information There's no good reason to deinterlace unless you want to go back to a film source.

Unless your ultimate destination is PC video such as a training seminar, etc.

[moon1234]

Originally posted by bb
That's true, but noise typically occurs in low-light conditions, no matter how good your CCD is. Low-light in this case refers to the amount of light the CCDs can capture, so to say "how much light gets inside the camcorder". Thus good and big object lenses can make lower-noise DV video than small ones with the same (low) light outside.

bb

With a good CCD sensor there should be virtually no noise in the absence of light. Put the lens cover on any consumer DV camera (Regardless of lens size) and film about ten seconds. Then bring that into your PC and examine the noise pattern.

Then do the same thing with a prosumer or prosessional 3CCD camera such as the Sony VX2100. You will see virtually no noise even in the complete absence of light.

More noise in the origional is due to inferior CCDs, as you stated in your post. Low light has no correlation to the level of noise. High quality CCDs can record virtually noise free video even in the complete absense of light.

You really do get what you pay for with CCD technology. If you really want clean, professional looking video you need to go for prosumer cameras and not the over the counter consumer models. How replaceable are your kids first years? You will never get them back, so why skimp on the technology to remember them?

Get a cheaper car, you can always upgrade. You will never get those precious moments back. How many of us look at photos taken of our families ancestors around the turn of the 20th century (1880-1910) and really appreciate them? How many of those photos were taken with an off the shelf camera? Virtually none of them were. The photos were taken in studios or outside with professional equipment of the time. The same rules should apply today.

[SimonSez07]

@Abaddon666

i use ffdshow to decode my dv avi's as you do, but i have found that with the newer versions of the package, you do not need to use DirectShowSource in AVISynth.

ffdshow can now decode with vfw, but you must go into "VFW Configuration" and under decoder, set DV from "disabled" to "libavcodec".

now you can decode dv type-2 directly from within vdub or cce or whatever without installing any other codec. and i think will decode to all (yv12, yuv2, and rgb) colorspaces

it would be great if ffdshow vfw decoder could be put in this comparison with panasonic, mainconcept, and canopus

[makoto916]

Has anyone had the opportunity to review the VFW DV Codec from Matrox? It ships with all of their RTX DV boards. The Codec doesn't need the board to work but unfortunately, while the codec is free, it is only available to download if you are a registered RTX user.

Nevertheless, has anyone done any testing with it? If not, if someone would share with me your procedure for testing, I'd be happy to supply a test sample.

I think the codec is worth checking out. I've been using it for a couple of years now and have found it to be superior to Mainconcept and Canopus, but I'm hardly an expert and would rather the experts here be the judge.

EDIT:

Actually posting this got me thinking so I did some of my own tests using rather unsophisticated means. I took the DV Stress Test picture from adamwilt.com and threw it into Premiere 1.5 and encoded a 15 frame video into Microsoft DV, Matrox DV, and Matrox DVCPRO50.

Here are the links to the AVIs: Matrox DV, Matrox DVCPRO50, and Microsoft DV. Note that I did these tests using the Matrox VFW DV and DVCPRO50 Codec and not on the system with the RTX100 board so that the tests weren't influenced by the hardware.

I don't know how to interpret the results. Just by loading the resulting AVI into Virtual Dub, the Matrox DV codec clearly handles solid color better as there are very few artificats in the solid areas. However, the Chroma Only section is absolutely terrible. You can at least read it with the MSDV Codec, but with the Matrox codec its just garbage. It's almost as if the MS Codec is anti-aliasing where the Matrox is not. But again I really don't know what I'm looking at so this is just casual observation.

The DVCPRO50 Codec on the otherhand is quite good, aside from some slight pixelization in the chroma text and hard curves.

Also, I don't know if Premiere had any influence on this test. Any insight is appreciated.

[SimonSez07]

@ makoto916 -

what is DVCPRO50? and what is the diference between that and the other matrox codec u tested. and how do you encode with microsoft dv. i do belive microsoft dv is NOT a codec but just a decoder filter.

it was a good idea to test more codes by the way. it actually might be interesting to test these codecs in their ability to decode dv also, and post the results of which is fastest, decodes to all three colorspaces without problems, and has the highest quality.

[makoto916]

In a nutshel, DVCPRO is an alternate DV methodology and DVCPRO50 is the "profesional" version with double the bitrate of standard DV (50mbps instead of 25). I believe JVC is one of the big DVCPRO pushers.

The codec I tested was Matrox's DV and DVCPRO codecs. I tested the encoding side of them, not the decoding, and matched them up against MS DV to see what was better. From my perspective it's hard to tell since I'm not as skilled in video as many of the others here, hence the reason for my post.

As for encoding in MS DV it is not a VFW codec in that you can't use it with any application. Only applications that support DirectShow will support this, but you can indeed encode into it. I hope that someday VirtualDub will support encoding into MS DV as well as other DirectShow codecs.

[FredThompson]

Enlarge and look at the upper left yellow arm of the robot.

[makoto916]

It certainly appears that the newer version handles saturated reds better. Theres less of a "patterned" look to it.

[WorBry]

Regarding the Matrox codecs - see my initial observations with DV/DVCAM (vfw version) in the following thread (11th post):

http://forum.doom9.org/showthread.php?s=&threadid=86422

Please dont give me a hard time if my "laymans" theoretical assumptions about color space conversion are off. At the end of the day, I'm just trying to get the best quality video. I havent tried the DVCPRO format yet.

I'd really appreciate it if someone could advise, when converting to DVD (for TV playback), what color adjustment method to use in TMPGenc Express to properly correct for the luminance shift "haze" that arises when using the Sony DV codec as decompressor. My experiences with that codec are noted in the same thread.

Cheers.

[Steve56]

I did also test the ffdshow livavcodec YV12 decoding versus DirectShow YUY2 decoding, but I think the YV12 decoded image is not as good (seems to have blurred chroma between the interlaced lines?!).

QuickTime DV -> DirectShowSource -> libavcodecYV12 -> VDubMod:


QuickTime DV -> DirectShowSource -> YUY2 -> VDubMod:


BTW, what made me wonder in the first was, that I could open the QuickTime DV streams directly with DirectShowSource in AviSynth, that didn't work in the past (I used DV File Converter then), maybe because of a present NeroVision Express QuickTime/DirectShow layer?

Steve56

[makoto916]

@WorBry - Actually I have the opposite happen here with Field order. The Matrox NTSC codec forces everything to Bottom Filed first and it's quite the pain when using NTSC DVDs which tend to be TFF. I wish I knew a way to have AVISynth detect field order as my output needs to be interlaced and not progressive for what I do with it.

@Steve56 - I don't know if Nero installs a DirectShow decoder for Quicktime, but I know that with FFDShow and 3IVX installed you can sucessfully decode QuicktimeDV via DirectShowSource in AVISynth. It actually works remarkably well.

[WorBry]

Makoto.

Here's an abstract from the KernelDeint AVS filter Info file that explains how to determine the field order:

"KernelDeint() takes the following named parameters:

order (0-1, default none!) This parameter defines the field order of the clip. It is very important to set this correctly. Use order=0 for bottom field first (bff). Use order=1 for top field first (tff). You must specify order; DGBob throws an exception if you omit this parameter.

It is essential to set the field order properly for correct rendering. Because setting it correctly is so important, you are strongly encouraged not to make assumptions about the field order of a clip, but rather to verify the field order using the following procedure.

To determine the field order, make an Avisynth script that serves the raw clip without any processing. If it were an AVI, then just AviSource() would be used. For our examples, we'll use AviSource(). Add a script line to separate the fields using top field first, as follows:

AviSource("your_clip.avi")
AssumeTFF().SeparateFields()

Now serve the script into VirtualDub and find an area with motion. Single step forward through the motion. Note whether the motion progresses always forward as it should, or whether it jumps back and forth as it proceeds. For example, if the field order is wrong, an object moving steadily from left to right would move right, then jump back left a little, then move right again, etc. If the field order is correct, it moves steadily to the right.

If the motion is correct with AssumeTFF().SeparateFields(), then your field order is top field first and you must set order=1. If the motion is incorrect, then your field order is bottom field first and you must set order=0. If you are want to double check things, you can use AssumeBFF.SeparateFields() to check correct operation for bottom field first."

Hope that helps.

[makoto916]

WorBry, thank you for the information. It is most helpful.

[WorBry]

Makoto916,

You're welcome.

I agree, its very strange that the Matrox DV/DVCAM codec outputs PAL as TFF and NTSC as BFF, as you say.

For my normal purposes I'm only using Matrox codec as a decompressor. When capturing and editing, I usually disable Matrox and use the internal Type II DV encoder in Ulead Video Studio. I got into this habit when using the Sony DV codec. Even if not selected for smart-rendering the edited DV clip, merely having the Sony DV codec enabled would result in edited segments (transitions etc) that were lighter than the unedited portion. In fact, I would get the same result even if the entire clip was completely recompressed. I havent checked to see whether the Matrox codec does the same - probably not, since it does not appear to be subject to luminance shifts. But, like I, said its a habit, I've got into.

For interests sake, I've just re-encoded a few of my PAL DV clips with the Matrox codec to see what happens to the field order and sure enough - TFF again. I had some notion that maybe the codec reverses BFF to TFF on encoding and then back to BFF on decompression, but obviously not

BTW - various forum threads I've come across discussing the Matrox codec refer to advanced configuration settings. Do you know how to access these settings. The Windows version of the Matrox Digisuite codecs package that I downloaded doesnt seem to have any such options, at least when opened in the VirtualDub Compression codec library. Is this feature only available in Premiere or something ?

Cheers.

[makoto916]

I'm unaware of any advanced setting with the Matrox codec. I loaded up FilterManager just to see and there doesn't appear to be anything special for it.

Also under Premiere Pro 1.5 when you select the Matrox codec for export the "Configure" button greys out indicating there are no additional settings to tweak.

So your guess is as good as mine.

[Lycaon]

Originally posted by Steve56
ffdshow libavcodec YV12 decoding...is not as good (seems to have blurred chroma between the interlaced lines?!)

That's because libavcodec is Converting the DV (YV12 4:1:1) into YV12 4:2:0. I wouldn't recommend you use libavcodec for DV material.

Does anyone know of a decoder that decodes in the Native 4:1:1? It seems most all of them, including microsoft and Mainconcept only support 4:2:2 and require the FixBrokenChromaUpsampling.

[whiskey]

Ok guys so if i have panasonic miniDV camcorder i should use codecs from panasonic or u recommend other stuff ???